Each Loot Box contains four randomly selected items that can be used to customize heroes or the player's profile. Items come in the Common, Rare, Epic, and Legendary quality levels, and every Loot Box includes at least one Rare or better item. Loot Box's contents are generated when the box is earned or bought, not when it is opened.[1] For example, any Loot Box acquired before installing the July 19, 2016 patch will not contain any of Ana's items.

The overall chances for an item to be Common, Rare, Epic and Legendary which was calculated by players based on apparent statistic are approximately 58.2%, 31.7%, 7.55% and 2.55%, respectively.[2][3] On 23 March, 2017, Blizzard published the official probability for Loot Box's items, which is:

A Rare item or above will be included in every box.

An Epic item and above will be included, on average, once in every 5.5 loot boxes.

A Legendary item will included, on average, once in every 13.5 boxes.[4]

To open a Loot Box, either navigate to the main menu and click the "Loot Box" option or bring up the Escape menu and click the bright orange "Open Loot Box" button (when possessing at least one Loot Box). Players can open one Loot Box at a time, and they'll have a chance to preview or equip new items before moving on to the next Loot Box.

In Overwatch (as in many games by Blizzard Entertainment), different colors are associated with different item qualities: Gray = Common, Light Blue = Rare, Pink = Epic, and Orange = Legendary.

Items from Loot Boxes include player icons, skins, emotes, sprays, voice lines, victory poses, and highlight intros, as well as credits that players can spend to unlock items of their choice.

Player Icons: Used to customize the avatar of the player profile. Player Icons reference heroes, abilities, miscellaneous in-game terms, or even other Blizzard games. All Player Icons come in Rare quality.

Skins: Skins are one of the most valuable items by far, and are generally more valuable than sprays or voice lines. They are used to change the appearance of heroes. Skins come in three qualities: Rare, Epic and Legendary.

Emotes: Another type of valuable item. They are used to perform an action through the use of the Communication Wheel. These are only for cosmetic purposes and have no effect on gameplay. Some emotes last longer than others, some have an infinite duration, unless interrupted. All Emotes come in Epic quality, except for a select few Legendary ones.

Sprays: Used to spray on a surface in the game. Sprays are based on heroes, maps, etc. Some sprays are not acquired through Loot Boxes, but achievements instead. All Sprays come in Common quality.

Voice Lines: Used to speak with teammates in the voice of heroes through use of the Communication Wheel. All Voice Lines come in Common quality.

Victory Poses: Used to customize the pose of heroes in the team's Victory photo finish. All Victory Poses come in Rare quality.

Highlight Intros: A valuable item to obtain. They are used to customize the animated introduction at the beginning of every Play of the Game or when viewing one's Highlight. All Highlight Intros come in Epic quality.

Credits: A pile of gold representing credits. Credits come in three qualities: Rare for 50, Epic for 150 and Legendary for 500. There is approximately 30% chance of a Loot Box containing a credit pile.[2]

If a Loot Box contains an item that is already in the player's collection, the player will receive compensation in credits. Duplicate items reward one-fifth of the cost of that item. In case of duplicate Player Icons, the compensation is 15, as Player Icons cannot be bought and have no value. For other items, the compensation is as below:

Duplicate items

Compensations

Common

5

Rare

15

Epic

50

Legendary

200

Note that, although the price for newly-introduced seasonal event items are thrice the price of normal item of the same rarity, their compensations for duplicates are still equal to normal items'.

For the seasonal events, Blizzard introduced a limited edition series of Loot Boxes. Any box earned through level up or purchase within an event's duration will become a seasonal event Loot Box instead of a normal Loot Box, and one seasonal event Loot Box will be awarded to the player upon launching the game during the event.

These special Loot Boxes are guaranteed to contain at least one item from the event's item pool. All other rules of Loot Boxes (rarity chance, duplication, etc.) are still active for the seasonal event Loot Boxes. Furthermore, the probability for event items and normal items are calculated separately; therefore, the chance of encountering Epic and Legendary items are higher than in normal Boxes.[5]

Items from the Summer Games 2016 series could only be acquired from these special Loot Boxes and could not be bought from the Hero Gallery. Starting in the Halloween Terror 2016 event, special items may be bought from the Hero Gallery at triple the price of normal items of the same rarity. Starting in the Summer Games 2017 event, special items which were available in the previous iteration of an event have their price reduced to the normal cost when the event returned.

Any unopened seasonal event boxes will remain in their original form after the event; these boxes will not be removed, will not turn into normal boxes, and will remain unopened. If they are opened after the event's conclusion, they will still yield special seasonal items.

The Golden Loot Box is the first promotional Loot Box in Overwatch, first given out between 20 June to 10 August, 2017. Each Golden Loot Box is guaranteed to contain a legendary skin. It is reported that players who received duplicated Genji's Oni skin and D.Va's Officer skin were able to contact Blizzard to receive a new Loot Box.

In order to obtain the Golden Loot Box, players have had to register for a Twitch Prime membership to receive one promotional code during certain select dates. The codes will expire 3 months after the generating date if they are not redeemed. Furthermore, one Battle.net account cannot redeem multiple Golden Loot Box codes.[6]

The 2018 Anniversary event gave out a Golden Lootbox, which had a guaranteed event Legendary, to every player who logged in during the event.

On the release of Wrecking Ball, Twitch Prime users could redeem 2 Loot Boxes guaranteed to give non-duplicate cosmetics for Wrecking Ball, provided the player has enough locked cosmetics for there to not be duplicates.

April 13, 2016 (beta)Patch: New Legendary skins have been added for several heroes, including: Genji, and Pharah.

April 6, 2016 (beta)Patch:Several new sprays have been added for Bastion, Mei, Mercy, Pharah, and Winston.

April 5, 2016 (beta)Patch:Several new sprays, player icons, and voice lines have been added; some of the less popular sprays and voice lines have been removed. New Legendary skins have been added for several heroes, including: Bastion, D.Va, Genji, Junkrat, Lúcio, Mei, Pharah, Reaper, Reinhardt, Roadhog, Soldier: 76, Widowmaker, Zarya.

March 8, 2016 (beta)Patch:Signature, cheer, and taunt emote rewards are now available for all heroes. Default emotes have been added for all heroes and are immediately available in the communications wheel. Several new sprays have been added. And New Legendary skins have been added for several heroes, including: Bastion, Lúcio, McCree, Pharah, Reinhardt, and Soldier: 76.

March 1, 2016 (beta)Patch:All sprays and voice lines are now considered “Common”. All player icons and victory poses are now considered “Rare” (excluding default icons and poses). “Rare” and “Epic” quantities of credits will now appear more frequently in Loot Boxes. “Legendary” quantities of credits will now appear less frequently in Loot Boxes. Fixed an issue with the lighting on several Loot Box rewards that caused skins and poses to appear darker than intended.